The Clown Knifefish can be found in the waters of Southeast Asia in countries like India, Indonesia, Thailand and Borneo. These fish get their names from the spots that line the sides of their body, which multiply as they age. These fish can grow up to be 3 feet long! Clown Knifefish are nocturnal and have the primitive ability to breathe air. They are often seen rising to the surface of the water to take a gulp of air.